Sequential Cobalt/Rhodium‐Catalyzed Tandem Cyclization of Aromatic Aldehydes with Acrylates for Preparing 3‐Substituted Phthalides in Oxygen Atmosphere and Neat Water

2021 ◽  
Author(s):  
Xin‐Ran Li ◽  
Wan‐Di Li ◽  
Wen‐Ting Wei ◽  
Juan Fan ◽  
Zhong‐Wen Liu ◽  
...  
Keyword(s):  
Aromatic Aldehydes ◽  
Oxygen Atmosphere ◽  
Neat Water ◽  
Tandem Cyclization

Ammonium Iodide-Catalyzed Radical-mediated Tandem Cyclization of Aromatic Aldehydes, Arylamines and 1,4-Dioxane

2021 ◽  
Author(s):  
Yunfeng Liao ◽  
Yiyan Yan ◽  
Hongrui Qi ◽  
Weijie Zhang ◽  
Yanjun Xie ◽  
...  
Keyword(s):  
Aromatic Aldehydes ◽  
Ammonium Iodide ◽  
Novel Approach ◽  
Tandem Cyclization ◽  
Three Components

We have developed a novel approach for the construction of 2-((2-arylquinolin-4-yl)oxy)ethan-1-ol derivatives by an NH4I-catalyzed radical-mediated tandem cyclization of three components including aromatic aldehydes, arylamines and 1,4-Dioxane. This strategy involves...

An efficient Sn(ii)-catalyzed one-pot synthesis of a 3-substituted azetidine-2,4-dione framework

2017 ◽  
Vol 15 (11) ◽  
pp. 2385-2391 ◽  
Author(s):  
Santosh S. Chavan ◽  
Mrudul V. Supekar ◽  
Pralhad A. Burate ◽  
Bapurao D. Rupanwar ◽  
Anil M. Shelke ◽  
...  
Keyword(s):  
Ethyl Cyanoacetate ◽  
Aromatic Aldehydes ◽  
Cyclization Reaction ◽  
One Pot ◽  
One Pot Synthesis ◽  
Tandem Cyclization

A novel Sn(ii)-catalyzed tandem cyclization reaction of aromatic aldehydes with ethyl cyanoacetate has been achieved to afford a series of 3-substituted azetidine-2,4-diones in good to excellent yields.

Photoconductivity in Vacuum Deposited Films of Silicon-Based Polymers

1996 ◽  
Vol 444 ◽  
Author(s):  
H. Okumoto ◽  
M. Shimomura ◽  
N. Minami ◽  
Y. Tanabe
Keyword(s):  
Charge Transfer ◽  
Chemical Modification ◽  
Electronic Transport ◽  
Hole Transport ◽  
Electron Acceptors ◽  
Oxygen Atmosphere ◽  
Dangling Bonds ◽  
Silicon Based ◽  
Deposited Films

AbstractSilicon-based polymers with σconjugated electrons have specific properties; photoreactivity for microlithography and photoconductivity for hole transport materials. To explore the possibility of combining these two properties to develop photoresists with electronic transport capability, photoconductivity of polysilanes is investigated in connection with their photoinduced chemical modification. Increase in photocurrent is observed accompanying photoreaction of poly(dimethylsilane) vacuum deposited films. This increase is found to be greatly enhanced in oxygen atmosphere. Such changes of photocurrent can be explained by charge transfer to electron acceptors from Si dangling bonds postulated to be formed during photoreaction.

COMBUSTION OF POROUS SILICON IN AN OXYGEN ATMOSPHERE WITH A PRESSURE FROM 2 TO 33 BAR

2020 ◽  
Vol 24 (4) ◽  
pp. 261-274
Author(s):  
Vitaly N. Mironov ◽  
Oleg G. Penyazkov ◽  
P. N. Krivosheyev ◽  
Y. A. Baranyshyn ◽  
E. S. Golomako ◽  
...  
Keyword(s):  
Porous Silicon ◽  
Oxygen Atmosphere

A New Dehydrogenase Specific Towards Aromatic Aldehydes From A Halophilic Bacterium

2003 ◽  
Vol 10 (5) ◽  
pp. 449-457 ◽  
Author(s):  
F. Cara ◽  
L. Alves ◽  
F. Girio ◽  
A. Salle ◽  
A. Capasso ◽  
...  
Keyword(s):  
Aromatic Aldehydes ◽  
Halophilic Bacterium

Chlorosulfonic Acid Supported Piperidine-4-carboxylic Acid (PPCA) Functionalized Fe3O4 Nanoparticles (Fe3O4-PPCA): The Efficient, Green and Reusable Nanocatalyst for the Synthesis of Pyrazolyl Coumarin Derivatives under Solvent-Free Conditions

2019 ◽  
Vol 22 (2) ◽  
pp. 123-128
Author(s):  
Setareh Habibzadeh ◽  
Hassan Ghasemnejad-Bosra ◽  
Mina Haghdadi ◽  
Soheila Heydari-Parastar
Keyword(s):  
Carboxylic Acid ◽  
Fe3o4 Nanoparticles ◽  
High Efficiency ◽  
Reaction Times ◽  
Chlorosulfonic Acid ◽  
Aromatic Aldehydes ◽  
Solvent Free ◽  
Magnetic Nanocatalyst ◽  
One Pot ◽  
Solvent Free Conditions

Background: In this study, we developed a convenient methodology for the synthesis of coumarin linked to pyrazolines and pyrano [2,3-h] coumarins linked to 3-(1,5-diphenyl-4,5- dihydro-1H-pyrazol-3-yl)-chromen-2-one derivatives using Chlorosulfonic acid supported Piperidine-4-carboxylic acid (PPCA) functionalized Fe3O4 nanoparticles (Fe3O4-PPCA) catalyst. Materials and Methods:: Fe3O4-PPCA was investigated as an efficient and magnetically recoverable Nanocatalyst for the one-pot synthesis of substituted coumarins from the reaction of coumarin with a variety of aromatic aldehydes in high to excellent yield at room temperature under solvent-free conditions. The magnetic nanocatalyst can be easily recovered by applying an external magnet device and reused for at least 10 reaction runs without considerable loss of reactivity. Results and Conclusion: The advantages of this protocol are the use of commercially available materials, simple and an inexpensive procedure, easy separation, and an eco-friendly procedure, and it shows good reaction times, good to high yields, inexpensive and practicability procedure, and high efficiency.

Microwave assisted synthesis of novel Pyrazole derivatives and their biological evaluation as anti-bacterial agents

2020 ◽  
Vol 23 ◽  
Author(s):  
Hadis Khodadad ◽  
Farhad Hatamjafari ◽  
Khalil Pourshamsian ◽  
Babak Sadeghi
Keyword(s):  
Antibacterial Activity ◽  
Aromatic Aldehydes ◽  
Catalytic Amount ◽  
Antibacterial Activities ◽  
Structural Features ◽  
Biological Evaluation ◽  
Aureus Strain ◽  
Microwave Assisted Synthesis ◽  
Pyrazole Derivatives ◽  
Microwave Assisted

Aim and Objective: Microwave-assisted condensation of acetophenone 1 and aromatic aldehydes 2 gave chalcone analogs 3, which were cyclized to pyrazole derivatives 6a-f via the reaction with hydrazine hydrate and oxalic acid in the presence of the catalytic amount of acetic acid in ethanol. Materials and Methods: The structural features of the synthesized compounds were characterized by melting point, FT-IR, 1H, 13C NMR and elemental analysis. Results: The antibacterial activities of the synthesized pyrazoles was evaluated against three gram-positive bacteria such as Enterococcus durans, Staphylococcus aureus, Bacillus subtilis and two gram-negative bacteria such as Escherichia coli and Salmonella typhimurium. Conclusion: All the synthesized pyrazoles showed relatively high antibacterial activity against S. aureus strain and none of them demonstrated antibacterial activity against E. coli.

Synthesis of 3-(Cyclohexylamino)-2-arylimidazo[1,2-a]pyridine-8- carboxylic Acids Via an Efficient Three-component Condensation Reaction between Cyclohexylisocyanide and 2-Aminopyridine-3-carboxylic Acid in the Presence of Aromatic Aldehyde

2018 ◽  
Vol 21 (4) ◽  
pp. 298-301 ◽  
Author(s):  
Ghasem Marandi
Keyword(s):  
Biological Sciences ◽  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
High Performance ◽  
Condensation Reaction ◽  
Aromatic Aldehydes ◽  
New Materials ◽  
One Pot ◽  
High Yields ◽  
Benzaldehyde Derivatives

Aim and Objective: The reaction of cyclohexylisocyanide and 2-aminopyridine-3- carboxylic acid in the presence of benzaldehyde derivatives in ethanol led to 3-(cyclohexylamino)-2- arylimidazo[1,2-a]pyridine-8-carboxylic acids in high yields. In a three component condensation reaction, isocyanide reacts with 2-aminopyridine-3-carboxylic acid and aromatic aldehydes without any prior activation. Material and Methods: The synthesized products have stable structures which have been characterized by IR, 1H, 13C and Mass spectroscopy as well as CHN-O analysis. Results: In continuation of our attempts to develop simple one-pot routes for the synthesis of 3- (cyclohexylamino)-2-arylimidazo[1,2-a]pyridine-8-carboxylic acids, aromatic aldehydes with divers substituted show a high performance. Conclusion: In conclusion, this study introduces the art of combinatorial chemistry using a simple one-pot procedure for the synthesis of new materials which are interesting compounds in medicinal and biological sciences.

Synthesis and Kinetics of Highly Substituted Piperidines in the Presence of Tartaric Acid as a Catalyst

2018 ◽  
Vol 21 (4) ◽  
pp. 302-311
Author(s):  
Younes Ghalandarzehi ◽  
Mehdi Shahraki ◽  
Sayyed M. Habibi-Khorassani
Keyword(s):  
Ambient Temperature ◽  
Tartaric Acid ◽  
Aromatic Aldehydes ◽  
One Pot ◽  
Rate Determining Step ◽  
State Approximation ◽  
Solvent Free Conditions ◽  
Steady State Approximation ◽  
Absorbance Changes ◽  
The One

Aim & Scope: The synthesis of highly substituted piperidine from the one-pot reaction between aromatic aldehydes, anilines and β-ketoesters in the presence of tartaric acid as a catalyst has been investigated in both methanol and ethanol media at ambient temperature. Different conditions of temperature and solvent were employed for calculating the thermodynamic parameters and obtaining an experimental approach to the kinetics and mechanism. Experiments were carried out under different temperature and solvent conditions. Material and Methods: Products were characterized by comparison of physical data with authentic samples and spectroscopic data (IR and NMR). Rate constants are presented as an average of several kinetic runs (at least 6-10) and are reproducible within ± 3%. The overall rate of reaction is followed by monitoring the absorbance changes of the products versus time on a Varian (Model Cary Bio- 300) UV-vis spectrophotometer with a 10 mm light-path cell. Results: The best result was achieved in the presence of 0.075 g (0.1 M) of catalyst and 5 mL methanol at ambient temperature. When the reaction was carried out under solvent-free conditions, the product was obtained in a moderate yield (25%). Methanol was optimized as a desirable solvent in the synthesis of piperidine, nevertheless, ethanol in a kinetic investigation had none effect on the enhancement of the reaction rate than methanol. Based on the spectral data, the overall order of the reaction followed the second order kinetics. The results showed that the first step of the reaction mechanism is a rate determining step. Conclusion: The use of tartaric acid has many advantages such as mild reaction conditions, simple and readily available precursors and inexpensive catalyst. The proposed mechanism was confirmed by experimental results and a steady state approximation.

1, 1’-Sulfinyldiethylammonium Bis (Hydrogen Sulfate) as a Recyclable Dicationic Ionic Liquid Catalyst for the Efficient Solvent-free Synthesis of 3, 4-Dihydropyrimidin-2(1H)-ones via Biginelli Reaction

2020 ◽  
Vol 23 (2) ◽  
pp. 157-167
Author(s):  
Zainab Ehsani-Nasab ◽  
Ali Ezabadi
Keyword(s):  
Ionic Liquid ◽  
Biginelli Reaction ◽  
Aromatic Aldehydes ◽  
Solvent Free ◽  
Hydrogen Sulfate ◽  
One Pot ◽  
Acidic Ionic Liquid ◽  
Brønsted Acidic Ionic Liquid ◽  
Solvent Free Conditions ◽  
Dicationic Ionic Liquid

Objective: A facile and efficient method for synthesis of 3, 4-dihydropyrimidin-2(1H)-ones via Biginelli reaction catalyzed by a novel dicationic Brönsted acidic ionic liquid, [(EtNH2)2SO][HSO4]2, has been successfully developed. Material and Method:: 3, 4-Dihydropyrimidin-2(1H)-ones were synthesized through one-pot condensation of aromatic aldehydes, ethyl acetoacetate, and urea under solvent-free conditions using [(EtNH2)2SO][HSO4]2 as a novel catalyst. The progress of the reaction was monitored by thin-layer chromatography (ethyl acetate / n-hexane = 1 / 5). The products have been characterized by IR, 1H NMR, 13C NMR, and also by their melting points. Results: In this research, a library of dihydropyrimidinone derivatives was synthesized via Biginelli reaction under solvent-free conditions at 120oC using [(EtNH2)2SO][HSO4]2 as a catalyst. Various aromatic aldehydes, as well as heteroaromatic aldehydes, were employed, affording good to high yields of the corresponding products and illustrating the substrate generality of the present method. In addition, the prepared dicationic Brönsted acidic ionic liquid can be easily recovered and reused. Conclusion: 1, 1’-Sulfinyldiethylammonium bis (hydrogen sulfate), as a novel dicationic ionic liquid, can act as a highly efficient catalyst for the synthesis of 3, 4-dihydropyrimidin-2(1H)-ones under solvent-free conditions.

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